Archive | 2019
Heartwood taper in northern red oak ( Quercus rubra L.)
Abstract
To better understand how the practice of long–term tree retention affects value, northern red oak (Quercus rubra L.) trees from the Menominee Indian Reservation in Wisconsin were harvested and examined for patterns of heartwood development in relation to several tree characteristics. A total of 69 mature northern red oak trees from three dbh size classes, small (34-47 cm, 20 trees), medium (48-60 cm, 20 trees), and large (≥ 61 cm, 29 trees), were logged and optimally bucked. Cross-sectional disks were then removed from the tops of the stumps and each log and were analyzed for patterns of change in heartwood radius. Four factors were found to have a statistically significant effect on heartwood radius: age of the tree, size class, height, and inside bark radius. The inside bark radius was the strongest predictor of heartwood radius. A 1 cm increase in inside bark radius led to approximately a 0.95 cm increase in heartwood radius. Increasing height had a small negative effect, with heartwood radius decreasing approximately 0.05 cm for each meter above ground. Age of the tree had a small positive effect of 0.0016 cm per year and was only significant in one expert model considered. These results provide consumers of oak logs and forest managers insight to the interior heartwood pattern and can lead to improved value assessments for northern red oak logs.